The present invention relates to beverage dispensing equipment, and more particularly to an improved ice chest and cold plate apparatus having a cold plate heat exchanger attached to the bottom surface of an ice storage container with a thermally conductive adhesive.
Ice cooled beverage dispensers for cooling soft drinks and other beverages are well known in the art. These beverage dispensers are known and used extensively in restaurants, bars, amusement parks, concession stands, movie theaters, and the like. The ice cooled beverage dispensers typically utilize an ice chest including a cast aluminum cold plate to chill carbonated water and flavoring syrups before mixing and dispensing these liquids in a finished soft drink. Such dispensers consist of a source of carbonated water, a source of flavoring syrup, a cold plate to cool the carbonated water and syrup, and dispensing valves to mix the carbonated water and syrup prior to dispensing the mixed beverage into a glass or cup.
Cold plates are known devices where melting ice is used to cool beverage liquids flowing through tubing in thermal contact with ice. The cold plate normally includes stainless steel tubes or coils embedded within a heat conducting aluminum casting. The cold plate or aluminum block is typically located at the bottom of an ice storage container. The coils are routed to appropriate mixing valves where the beverages are dispensed. The ice storage container thus serves the dual purpose of storing ice to dispense with the beverages and containing ice to cool fluids flowing through the coils.
This type of dispenser is very popular and reliable because it does not require an electromechanical refrigeration system, it is relatively inexpensive, it is portable, it does not require electricity, and it is very efficient. However, there are problems associated with the prior art ice cooled beverage dispensers. The construction of certain prior art ice chests and cold plates can lead to growth of mold and fungus in crevices and other areas of the ice chest which are difficult to clean. Generally the aluminum cold plate is fitted into an opening in the bottom of the stainless steel ice chest, and it is the seams or crevices between the aluminum and stainless where such problems can most commonly arise.
Another problem is the high cost of construction and labor involved with cutting the bottom out of an ice chest and inserting a cold plate therein, or manufacturing an ice chest with a cold plate at the bottom of the ice chest. Most prior art ice chests have an open bottom for receiving a cold plate. With the bottom of the ice chest closed by the cold plate, the ice chest can be repeatedly filled with ice to maintain a low temperature of the cold plate. In this configuration, the aluminum from the cold plate is in direct contact with the ice. This direct contact between the aluminum and the ice is undesirable because the surface of the aluminum is not sufficiently smooth to prevent the buildup of dirt within the inherent crevices of the material.
For example, U.S. Pat. No. 4,678,104 to Pritchett discloses a cooling system for dispensing beverages having an ice tub with an open bottom to receive a cold plate. The cold plate is bolted to the sidewalls of the tub to form the bottom of the tub. U.S. Pat. No. 4,958,505 to Swanson discloses an ice cooled beverage dispenser with a cold plate attached to the open bottom of a tubular ice bin liner. The cold plate is attached to the sidewalls of the ice bin liner with rivet type fasteners or screws.